Ask Hackaday

The endless trenches of digital worlds are filled with hardcore gamers from all walks of life. They can be found exploring post-apocalyptic Boston in Fallout 4, and commanding Sgt. Recker through a war-torn landscape in Battlefield 4 for hours on end. Their portal into these vast digital worlds come via some sort of computer system.

What type of computer system used is a point of contention between many gamers, and is typically divided between console versus PC. I will not dare to drag you into the captious arguments between the two, but instead we will focus on something that has something in common with our world — how does a previously non-technical console enthusiast cross over and build a gaming PC?

Many hackers have built computers from scratch and [Adam Fabio] just covered a bunch of custom laptop builds this morning. People with such skills can easily build a high-end gaming PC. But what about people without such skills? Can a console gamer with no technical background build a high-end PC gaming system?

Inspiration for this article came after reading something [Emanuel Maiberg] published over the summer on Motherboard. Why someone writing for a publication called Motherboard would have trouble building a gaming rig is beyond me. Certainly I think his starting assumptions are questionable. He asserts that you need an unreasonable amount of time and money to attempt one of these projects. But gaming rigs can be purchased fully-assembled — those that build them are doing it out of passion.

The question is this: How far should engineers go to make a technical product easier to use for a non-technical person? If I order an engine for a hot rod, it can be assumed that I know to hook up the gas line without specifically being told to do so. After all, a person who’s going to put an engine in a hot rod probably knows a thing or two about engines.

I think that building a desktop PC has never been easier. We’ve now had 30 years of evolution to help weed out the “slow learners” when it comes to manufacturers. The Internet is a lot easier to use for answers than it used to be, and we have faster means of connecting with communities of experts than ever before.

That said, the neighborhood computer store is beginning to go the way of the dodo. There is an entire generation of “mobile-first” users who will give you a blank stare if you start talking about “desktop computing”. And familiarity with the fact that computer customization is even possible is beginning to fade; if all you’ve ever used are tablets and smartphones “upgrade” and “customization” are software terms, not hardware possibilities.

So we turn it over to you. Are gaming PCs hard to build? Have engineering practices and design choices made it easier than it used to be to get into it? What do you think is happening with the average skill level for working with computers now compared to when you had to open the case to add a modem to your machine? Let us know what you think in the comments below.

This is a tale of old CPUs, intensive SMD rework, and things that should work but don’t.

Released in 1994, Apple’s Powerbook 500 series of laptop computers were the top of the line. They had built-in Ethernet, a trackpad instead of a trackball, stereo sound, and a full-size keyboard. This was one of the first laptops that looked like a modern laptop.

The CPU inside these laptops — save for the high-end Japan-only Powerbook 550c — was the 68LC040. The ‘LC‘ designation inside the part name says this CPU doesn’t have a floating point unit. A few months ago, [quarterturn] was looking for a project and decided replacing the CPU would be a valuable learning experience. He pulled the CPU card from the laptop, got out some ChipQuick, and reworked a 180-pin QFP package. This did not go well. The replacement CPU was sourced from China, and even though the number lasered onto the new CPU read 68040 and not 68LC040, this laptop was still without a floating point unit. Still, it’s an impressive display of rework ability, and generated a factlet for the marginalia of the history of consumer electronics.

Faced with a laptop that was effectively unchanged after an immense amount of very, very fine soldering, [quarterturn] had two choices. He could put the Powerbook back in the parts bin, or he could source a 68040 CPU with an FPU. He chose the latter. The new chip is a Freescale MC68040FE33A. Assured by an NXP support rep this CPU did in fact have a floating point unit, [quarterturn] checked the Mac’s System Information. No FPU was listed. He installed NetBSD. There was no FPU installed. This is weird, shouldn’t happen, and now [quarterturn] is at the limits of knowledge concerning the Powerbook 500 architecture. Thus, Ask Hackaday: why doesn’t this FPU work?

Magnetic gears are surprisingly unknown and used only in a few niche applications. Yet, their popularity is on the rise, and they are one of the slickest solutions for transmitting mechanical energy, converting rotational torque and RPM. Sooner or later, you’re bound to stumble upon them somewhere, so let’s check them out to see what they are and what they are good for.

The ESP8266 is the reigning WiFi wonderchip, quickly securing its reputation as the go-to platform for an entire ecosystem of wireless devices. There’s nothing that beats the ESP8266 on a capability vs. price comparison, and this tiny chip is even finding its way into commercial products. It’s also a fantastic device for the hardware tinkerer, leading to thousands of homebrew projects revolving around this tiny magical device.

In every technical document, summary, and description of the ESP8266, the ESP8266 is said to be a 3.3V part. While we’re well into the age of 3.3V logic, there are still an incredible number of boards and hardware that still operate using 5V logic. Over on the Hackaday.io stack, [Radomir] is questioning this basic assumption. He’s wondering if the ESP8266 is 5V tolerant after all. If it is, great. We don’t need level converters, and interfacing the ESP to USB TTL serial adapters becomes much easier. Yes, you’ll still need to use a regulator if the rest of your project is running at 5V, but if the pins are 5V tolerant, interfacing the ESP8266 with a variety of hardware becomes very easy.

[Radomir]’s evidence for the possibility of 5V tolerant inputs comes from a slight difference in the official datasheet from Espressif, and the datasheet translated by the community before Espressif realized how many of these chips they were going to sell.

The best evidence of 5V tolerant pins might come from real-world experience — if you can drive a pin with 5V for months on end without it failing, there might be something to this claim. It’s not definitive, though; just because a device will work with 5V input pins for a few months doesn’t mean it won’t fail in the future. So far a few people have spoken up and presented ESPs directly connected to the 5V pin of an Arduino that still work after months of service. If this is evidence of 5V tolerant design or simply luck is another matter entirely.

While the official datasheet from Espressif lists a maximum VIH of 3.3V, maximum specs rarely are true maximums — you can always push a part harder without things flying apart at the seams. Unfortunately, unless we hear something from the engineers at Espressif, we won’t know if the ESP8266 was designed to be 5V tolerant, if it can handle 5V signals reliably, or if 5V signals are a really good way to kill a chip eventually.

Lucky for us — and this brings us to the entire point of an Ask Hackaday column — a few Espressif engineers read Hackaday. They’re welcome to pseudonymously chime in below along with the rest of the peanut gallery. Failing that, the ESP8266 has been decapped; are there any die inspection wizards who can back up a claim of 5V tolerance for the GPIO? We’d also be interested in hearing any ideas for stress testing pin tolerance.

If you’ve watched the tech news these last few months, you probably have noticed the rumors that Apple is expected to dump the headphone jack on the upcoming iPhone 7. They’re not alone either. On the Android side, Motorola has announced the Moto Z will not have a jack. Chinese manufacturer LeEco has introduced several new phones sans phone jack. So what does this mean for all of us?

This isn’t the first time a cell phone company has tried to design out the headphone jack. Anyone remember HTC’s extUSB, which was used on the Android G1? Nokia tried it with their POP Port. Sony Ericsson’s attempt was the FastPort. Samsung tried a dizzying array of multi-pin connectors. HP/Palm used a magnetic adapter on their Veer. Apple themselves tried to reinvent the headphone jack by recessing it in the original iPhone, breaking compatibility with most of the offerings on the market. All of these manufacturers eventually went with the tried and true ⅛” headphone jack. Many of these connectors were switched over during an odd time in history where Bluetooth was overtaking wired “hands-free kits”, and phones were gaining the ability to play mp3 files.

When you learn to solder, you are warned about the pitfalls of creating a solder joint. Too much solder, too little solder, cold joints, dry joints, failing to “wet” the joint properly, a plethora of terms are explained if you read one of the many online guides to soldering.

Unsurprisingly it can all seem rather daunting to a novice, especially if they are not used to the dexterity required to manipulate a tool on a very small-scale at a distance. And since the soldering iron likely to be in the hands of a beginner will not be one of the more accomplished models with fine temperature control and a good tip, it’s likely that they will experience most of those pitfalls early on in their soldering career.

As your soldering skills increase, you get the knack of making a good joint. Applying just the right amount of heat and supplying just enough solder becomes second nature, and though you still mess up from time to time you learn to spot your errors and how to rework and fix them. Your progression through the art becomes a series of plateaux, as you achieve each new task whose tiny size or complexity you previously thought rendered it impossible. Did you too recoil in horror before your first 0.1″ DIP IC, only to find it had been surprisingly easy once you’d completed it?

A few weeks ago we posted a Hackaday Fail of the Week, revolving around a soldering iron failure and confirmation bias leading to a lengthy reworking session when the real culprit was a missing set of jumpers. Mildly embarrassing and something over which a veil is best drawn, but its comments raised some interesting questions about bad solder joints. In the FoTW case I was worried I’d overheated the joints causing them to go bad, evaporating the flux and oxidising the solder. This was disputed by some commenters, but left me with some curiosity over bad solder joints. We all know roughly how solder joints go wrong, but how much of what we know is heresay? Perhaps it is time for a thorough investigation of what makes a good solder joint, and the best way to understand that would surely be to look at what makes a bad one.

If you’re a long-time Hackaday reader like we are, you’ll certainly remember a rash of projects from around ten years ago that all (mis-)used an LED as a light sensor. The idea wasn’t new, but somehow it made the rounds and insinuated itself into our collective minds. Around the same time, a cryptographic cipher with an exceptionally small memory footprint was also showing up in hacker projects: TEA (Tiny Encryption Algorithm).

This old project by [Marcin Bojanczyk], [Chris Danis], and [Brian Rogan] combines both the LED-as-light-sensor meme and TEA to make a door-entry keyfob that works over visible light. And they do so using almost nothing — a few LEDs and just over 2Kb of code. It’s pretty sweet.

Which brings us to the question: where are they (LED-sensors and TEA) now?

But our own experience with LEDs as light sensors is that the results are extremely variable across different LEDs. Code that works with water-clear red LEDs might not work with the ones that come in red-tinted plastic, for instance. Is that why they went extinct?Similarly, the TEA family of ciphers showed up in a bunch of projects around this time, from the badge for the HOPE conference in 2010 to a widely used RFM12B radio library. There are a couple of attacks on XXTEA, but they only affect reduced-round versions of the cipher, and rely on a tremendous amount of intercepted data — more than we’d see in a home-automation network over years.

Over the last five years or so, there’s been a lot more Internet of Things, which means using standard Internet-style encryption methods (AES and so on) that are widespread on non-memory-constrained computers. Is that what happened to XXTEA?

Anyway, we got tipped off to a project that combined a few of our favorite (old) ideas in one, so we thought that we’d share. Thanks [Blue Smoke] for the walk down memory lane. Any of you out there keeping the flame(s) alive? Have you used sensing LEDs or XXTEA? Are those projects still going, or do you have any future projects planned with these tricks still up your sleeve? Let us know in the comments below.